Dropbox Fax preview removes form layout after sending (only filled text visible)

Hi,

I noticed a strange issue with Dropbox Fax preview when sending a PDF form.

I uploaded a filled IRS form. The original PDF displays correctly in Adobe Acrobat, Edge, and Chrome, including all table lines, labels, and layout.

When I upload the document to Dropbox Fax, the preview looks completely normal. The form layout, table lines, and labels are all visible.

However, after the fax is sent and I view the document again in the "Sent" preview, most of the form layout disappears and only the text fields I filled remain visible. It looks like the background form layer or table lines are not rendered anymore.

Additional details:

- The original PDF renders correctly in Acrobat and browsers.

- The preview before sending looks correct.

- The issue only appears in the preview after the fax is sent.

- I also tried flattening the PDF before uploading, but the sent preview still shows the same behavior.

- If I download the document from the preview and open it locally, the layout appears normal again.

My question is: does the fax transmission use the original PDF rendering, or does it rely on the preview rendering shown after sending?

I just want to confirm whether the recipient will receive the full document layout (tables and labels), or if they will only see the text fields.

Thanks!